Electrochemical machining device

Abstract

The discharge electrode (130) has an electrode surface (131) along a machined surface of one of the plurality of blades. The first nozzle (134) is disposed adjacent to the discharge electrode (130). The first nozzle (134) has a first discharge port (132) that discharges electrolyte between the electrode surface (131) and the machined surface along the electrode surface (131).

Description

Technical Field

[0001] This invention relates to an electrolytic machining apparatus. Background Technology

[0002] As a prior art document that discloses the structure of an electrolytic machining apparatus for an impeller, there is Japanese Patent Application Publication No. 1-222820 (Patent Document 1). The electrolytic machining apparatus described in Patent Document 1 has a pair of generally blade-shaped machining electrodes with blade machining surfaces, and a liquid guide groove that opens towards the middle of the roots of the two machining electrodes as an electrolyte supply path.

[0003] Patent Document 1: Japanese Patent Application Publication No. 1-222820

[0004] Patent Document 1 describes an electrolytic machining apparatus that forms multiple blades by electrolytically machining multiple blades one by one using a pair of machining electrodes, with the electrolyte supplied at the midpoint between the machining electrodes. When machining an impeller in this manner, the machining time sometimes becomes longer, and the distribution of the electrolyte supplied between the machining electrodes becomes uneven, resulting in reduced machining accuracy. Summary of the Invention

[0005] The present invention was made in view of the above-mentioned problems, and its purpose is to provide an electrochemical machining apparatus that can shorten the processing time and process impellers with high precision.

[0006] The electrolytic machining apparatus according to the present invention is an electrolytic machining apparatus for electrolytically machining an impeller having multiple blades roughly machined along its outer periphery. The electrolytic machining apparatus includes a discharge electrode and a first nozzle. The discharge electrode has an electrode surface along the machined surface of one of the multiple blades. The first nozzle is disposed adjacent to the discharge electrode. The first nozzle has a first outlet for ejecting electrolyte along the electrode surface between the electrode surface and the machined surface.

[0007] In one embodiment of the invention, the electrolytic machining apparatus further includes a second nozzle. The second nozzle is disposed above the discharge electrode. The second nozzle has a second outlet for ejecting electrolyte from between the upper counter electrode surface and the surface being machined.

[0008] In one embodiment of the invention, the first nozzle and the second nozzle each have an electrolyte flow path. A rectifier mechanism is provided in the flow path of at least one of the first nozzle and the second nozzle.

[0009] In one embodiment of the invention, the discharge electrode and the first nozzle are integrally formed and detachably connected.

[0010] In one embodiment of the invention, the discharge electrode and the second nozzle are integrally formed and detachably mounted together.

[0011] According to the present invention, the processing time can be shortened and the impeller can be processed with high precision. Attached Figure Description

[0012] Figure 1 This is a top view showing the state of the electrochemical machining apparatus according to one embodiment of the present invention before the start of machining.

[0013] Figure 2 It means Figure 1 A three-dimensional diagram of the structure of the electrolytic machining apparatus.

[0014] Figure 3 It means Figure 2 A longitudinal sectional view of the structure of the electrolytic machining apparatus.

[0015] Figure 4 This is a top view showing the state in which multiple discharge electrodes in an electrochemical machining apparatus according to an embodiment of the present invention are respectively moved to the radially inner side of the rotation axis.

[0016] Figure 5 This is a perspective view showing the structure of the discharge electrode, the first nozzle, and the second nozzle included in an electrolytic processing apparatus according to an embodiment of the present invention.

[0017] Figure 6 Viewed from the direction of arrow VI Figure 5 Front view of the discharge electrode, the first nozzle, and the second nozzle.

[0018] Figure 7 This is a perspective view showing the structure of the discharge electrode included in an electrochemical processing apparatus according to an embodiment of the present invention.

[0019] Figure 8 This is a perspective view showing the structure of the first nozzle included in an electrolytic processing apparatus according to an embodiment of the present invention.

[0020] Figure 9 This is a perspective view showing the structure of the second nozzle included in an electrolytic processing apparatus according to an embodiment of the present invention.

[0021] Figure 10 This is a top view showing the structure of the first nozzle involved in the first modified example.

[0022] Figure 11 This is a partial perspective view showing the periphery of the first nozzle outlet of the electrolytic machining apparatus involved in the second modified example, viewed from the front side.

[0023] Figure 12 This is a partial perspective view showing the periphery of the second nozzle of the electrolytic machining apparatus involved in the third modified example, viewed from below. Detailed Implementation

[0024] Hereinafter, an electrochemical processing apparatus according to an embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, the same or equivalent parts in the drawings will be labeled with the same reference numerals, and their descriptions will not be repeated.

[0025] Figure 1 This is a top view showing the state of the electrochemical machining apparatus according to one embodiment of the present invention before the start of machining. Figure 2 It means Figure 1 A three-dimensional diagram of the structure of the electrolytic machining apparatus. Figure 3 It means Figure 2 A longitudinal sectional view of the structure of the electrolytic machining apparatus. Figure 1 and Figure 3 The clamping mechanism described later in the figure is not shown. Figure 2 and Figure 3 The diagram only shows one of the multiple discharge electrodes.

[0026] like Figures 1-3 As shown, an electrolytic machining apparatus 100 according to one embodiment of the present invention is used for electrolytic machining of an impeller 10 having a plurality of blades 11 roughly machined along its outer periphery. The impeller 10 is, for example, made of titanium alloy. The impeller 10 is roughly machined, for example, by casting. The impeller 10 is used, for example, as a turbine. Each of the plurality of blades 11 has a machined surface 12 that is twisted and bent. In this embodiment, the impeller 10 has 9 blades 11. However, the number of blades 11 of the impeller 10 is not limited to 9, and can be more than 9.

[0027] The electrochemical machining apparatus 100 includes a support platform 110, a rotating shaft 120, and multiple discharge electrodes 130. The support platform 110 detachably supports the impeller 10. The rotating shaft 120 holds the support platform 110 in a rotatable manner. The support platform 110 is detachably connected to the rotating shaft 120. The rotating shaft 120 is connected to a rotary drive unit (not shown).

[0028] Multiple discharge electrodes 130 are arranged at equal intervals on a circumference centered on the rotation axis 120, and are configured to contact and separate from each of the multiple blades 11. In this embodiment, the electrolytic processing apparatus 100 includes nine discharge electrodes 130. One discharge electrode 130 is configured to contact and separate from each blade 11.

[0029] The discharge electrode 130 has an electrode surface 131 along the machined surface 12 of the blade 11. That is, the plurality of discharge electrodes 130 each have an electrode surface 131 along the machined surface 12 of a corresponding blade 11 among the plurality of blades 11. The electrode surface 131 is twisted and bent.

[0030] The electrochemical machining apparatus 100 also includes a plurality of electrode holders 170 and a plurality of positioning plates 140. The discharge electrode 130 is held by the electrode holder 170 in a manner that allows it to move radially along the rotation axis 120. The plurality of electrode holders 170 hold the plurality of discharge electrodes 130 in a one-to-one correspondence. In this embodiment, the electrochemical machining apparatus 100 includes nine electrode holders 170. Each of the nine electrode holders 170 is configured to slide linearly.

[0031] Multiple discharge electrodes 130 are detachably connected to corresponding electrode holders 170 among multiple electrode holders 170. In this embodiment, a through hole is provided on the discharge electrode 130. The discharge electrode 130 is fastened to the electrode holder 170 by a bolt 160 inserted through the through hole.

[0032] An insulating plate 150 is disposed on the upper surface of each of the plurality of electrode holders 170. The insulating plate 150 provides electrical insulation between the discharge electrode 130 and the electrode holder 170. The insulating plate 150 is made of, for example, an insulating resin such as epoxy resin.

[0033] The positioning plate 140 is fixed on the insulating plate 150. The positioning plate 140 has: a flat upper surface on which the discharge electrode 130 is placed, a side wall that is in contact with the side of the discharge electrode 130, and a rear wall that is in contact with the end face of the root side of the discharge electrode 130.

[0034] The discharge electrode 130, mounted on the upper surface of the positioning plate 140, is positioned on the electrode holder 170 by means of the sidewall of the positioning plate 140 being in contact with the side of the discharge electrode 130 and the rear wall of the positioning plate 140 being in contact with the end face of the root side of the discharge electrode 130. That is, the plurality of positioning plates 140 position the plurality of discharge electrodes 130 one-to-one on the plurality of electrode holders 170. In addition, the position of the discharge electrode 130 can be finely adjusted by inserting a shim into the gap between the discharge electrode 130 and the positioning plate 140.

[0035] When the discharge electrode 130 moves to the radially inner side of the rotating shaft 120 as described later, the electrode surface 131 of the discharge electrode 130, which is positioned on the electrode holder 170, is located facing each other with a gap between it and the machined surface 12 of the impeller 10 of the workpiece.

[0036] The electrochemical machining apparatus 100 also includes a linear drive unit 180 that radially drives the electrode holder 170 along the rotation axis 120. In this embodiment, nine linear drive units 180 are provided, and each linear drive unit 180 is connected to the electrode holder 170.

[0037] like Figure 2As shown, the electrolytic machining apparatus 100 also includes a clamping mechanism 190. The clamping mechanism 190 is configured to be movable in the vertical direction and to press and clamp the impeller 10 supported by the support table 110 from above.

[0038] Figure 4 This is a top view showing the state in which multiple discharge electrodes in an electrochemical machining apparatus according to an embodiment of the present invention are respectively moved to the radially inner side of the rotation axis. Figure 4 In the diagram, only the discharge electrode 130 is moved to the radially inner side of the rotation axis.

[0039] The electrode holder 170 is brought close to the impeller 10 by the linear drive unit 180, thereby... Figure 4 As shown, the discharge electrode 130 moves to the radially inner side of the rotation axis 120. As a result, the electrode surface 131 of the discharge electrode 130 faces each other with a gap between it and the workable surface 12 of the blade 11 being processed.

[0040] Subsequently, by utilizing the rotary drive unit, the rotating shaft 120 is directed towards... Figure 2 Rotating in the direction indicated by arrow R, the electrode surface 131 approaches and faces the work-processed surface 12. In this embodiment, the electrode surfaces 131 of each of the nine discharge electrodes 130 simultaneously approach and face each other relative to the work-processed surfaces 12 of each of the nine blades 11. Electrolytic machining is performed by applying voltage to the discharge electrodes 130 in this state. In the blades 11 that have undergone electrolytic machining, the thickness decreases from the thickness formed during rough machining, and the surface roughness of the work-processed surface 12 becomes smooth.

[0041] Here, the structure of the discharge electrode 130 in the electrolytic processing apparatus 100 according to this embodiment will be described in detail.

[0042] Figure 5 This is a perspective view showing the structure of the discharge electrode, the first nozzle, and the second nozzle included in an electrolytic processing apparatus according to an embodiment of the present invention. Figure 6 Viewed from the direction of arrow VI Figure 5 Front view of the discharge electrode, the first nozzle, and the second nozzle. Figure 7 This is a perspective view showing the structure of the discharge electrode included in an electrochemical processing apparatus according to an embodiment of the present invention. Figure 8 This is a perspective view showing the structure of the first nozzle included in an electrolytic processing apparatus according to an embodiment of the present invention. Figure 9 This is a perspective view showing the structure of the second nozzle included in an electrolytic processing apparatus according to an embodiment of the present invention.

[0043] like Figures 5-9As shown, the electrolytic processing apparatus 100 also includes a first nozzle 134 and a second nozzle 136 that are integrally formed with respect to the discharge electrode 130. The discharge electrode 130 is composed of a conductive member. The first nozzle 134 and the second nozzle 136 are each made of an insulating resin such as epoxy resin.

[0044] However, the discharge electrode 130, the first nozzle 134, and the second nozzle 136 can also be made of a single conductive component. For example, conductive materials can be used to make the discharge electrode 130, the first nozzle 134, and the second nozzle 136 integrally and inseparably formed using a 3D printer or similar means.

[0045] like Figure 5 and Figure 6 As shown, the first nozzle 134 is arranged adjacent to the discharge electrode 130. In this embodiment, nine first nozzles 134 are arranged adjacent to one corresponding discharge electrode 130 among the nine discharge electrodes 130.

[0046] like Figure 4 As shown, the first nozzle 134 has a first outlet 132, which sprays electrolyte between the electrode surface 131 and the work-processed surface 12 when the electrode surface 131 and the work-processed surface 12 are close to each other and facing each other. When viewed from the front, the first outlet 132 has a shape along the electrode surface 131. The first nozzle 134 has a recess 135 on the side opposite to the electrode surface 131 side at the end of the first outlet 132 side.

[0047] The second nozzle 136 is positioned above the discharge electrode 130. For example... Figure 4 As shown, the second nozzle 136 has a second outlet 133, which sprays electrolyte from above between the electrode surface 131 and the work-processed surface 12 when they are close to each other and facing each other. Viewed from above, the second nozzle 136 is bent at the bend 137, and the second outlet 133 is located above the electrode surface 131. Viewed from below, the second outlet 133 has a shape that follows the electrode surface 131.

[0048] like Figure 7 As shown, the discharge electrode 130 has a main body portion 130a that engages with the first nozzle 134 and the second nozzle 136, respectively. Figure 8 As shown, the first nozzle 134 has an electrolyte flow path formed inside towards the first nozzle outlet 132, and has a first engaging portion 134a that engages with the main body 130a. The discharge electrode 130 and the first nozzle 134 are integrally formed and detachably mounted together.

[0049] like Figure 9As shown, the second nozzle 136 has an electrolyte flow path formed inside, leading to the second nozzle outlet 133, and has a second engaging portion 136a that engages with the main body 130a. The discharge electrode 130 and the second nozzle 136 are integrally formed and detachably mounted together.

[0050] Figure 10 This is a top view showing the structure of the first nozzle involved in the first modified example. For example... Figure 10 As shown, the first nozzle 234 in the first modified example has an electrolyte flow path formed inside, which is an inlet 231 for the electrolyte to flow into and a first outlet 132, and has a first engaging portion 234a that engages with the main body portion 130a.

[0051] A flow rectifying mechanism is provided in the electrolyte flow path of the first nozzle 234. In a first modification, the first nozzle 234 is provided with a first narrowing portion 232 and a second narrowing portion 233. Therefore, the electrolyte flow path of the first nozzle 234 is tortuous from the inlet 231 to the first outlet 132, and the inlet 231 and the first outlet 132 are not connected in a straight line. Furthermore, the structure of the flow rectifying mechanism is not limited to the narrowing portion; any structure that can ensure a uniform distribution of the electrolyte ejected from the first outlet 132 is acceptable. Alternatively, the flow rectifying mechanism can also be provided in the second nozzle 136. When the flow rectifying mechanism is provided in the second nozzle 136, a uniform distribution of the electrolyte ejected from the second outlet 133 can be achieved.

[0052] Figure 11 This is a partial perspective view showing the periphery of the first nozzle outlet of the electrolytic machining apparatus involved in the second modified example, viewed from the front side. Figure 11 As shown, the first nozzle 334 of the electrolytic machining apparatus according to the second modification is composed of a wall surface 139 that is continuous with the electrode surface 131 of the discharge electrode 130, a facing surface 332a in the first nozzle 334 that is spaced apart from the wall surface 139 and facing each other, a first connecting surface 332b and a second connecting surface 332c that connect the wall surface 139 and the facing surface 332a to each other.

[0053] In the second modification, the electrolyte ejected from the first outlet 332 of the first nozzle 334 can be continuously supplied from the wall surface 139 along the electrode surface 131 to the space between the electrode surface 131 and the work-on-machine surface 12. This allows for a more uniform distribution of electrolyte between the electrode surface 131 and the work-on-machine surface 12, enabling high-precision machining of the impeller 10.

[0054] Figure 12 This is a partial perspective view showing the periphery of the second nozzle's second outlet of the electrolytic machining apparatus involved in the third modified example, viewed from below. Figure 12As shown, when viewed from below, the second nozzle 436 of the electrolytic machining apparatus according to the third modification has a generally circular second outlet 433. The opening area of ​​the second outlet 433 is larger than that of the second outlet 133 according to one embodiment. This reduces the flow rate of the electrolyte ejected from the second outlet 433 and allows for targeted supply of electrolyte to the portion between the electrode surface 131 and the work-processed surface 12 where the electrolyte ejected from the first outlet 132 is less likely to diffuse.

[0055] In one embodiment of the electrochemical machining apparatus 100, an electrochemical machining apparatus is used to electrochemically machine an impeller 10 having multiple blades 11 roughly machined along its outer periphery. After the multiple discharge electrodes 130 are moved to the radially inner side of the rotating shaft 120, the rotating shaft 120 rotates, thereby performing electrochemical machining with the electrode surface 131 and the machined surface 12 approaching each other and facing each other. As a result, multiple blades 11 of the roughly machined impeller 10 can be electrochemically machined simultaneously, thus shortening the machining time and suppressing inconsistencies in the machining accuracy of the multiple blades 11, thereby machining the impeller 10 with high precision.

[0056] In an embodiment of the electrochemical machining apparatus 100 of the present invention, a first nozzle 134 disposed adjacent to the discharge electrode 130 has a first spray outlet 132 that sprays electrolyte between the electrode surface 131 and the work-to-be-machined surface 12 along the electrode surface 131. This allows for the uniform distribution of electrolyte between the electrode surface 131 and the work-to-be-machined surface 12, enabling high-precision machining of the impeller 10.

[0057] In an embodiment of the electrolytic machining apparatus 100 of the present invention, the first nozzle 134 has a recess 135 on the side opposite to the electrode surface 131 at the end on the first nozzle outlet 132 side. Figure 4 As shown, when the electrode surface 131 and the work surface 12 are close to each other and facing each other, the recess 135 can suppress interference between the adjacent discharge electrodes 130 and the first nozzle 134.

[0058] In an embodiment of the electrochemical machining apparatus 100, the support table 110 is detachably connected to the rotation shaft 120. This allows the support table 110, which has been damaged by electrochemical machining, to be removed from the rotation shaft 120 and replaced.

[0059] In an embodiment of the electrochemical machining apparatus 100 according to the present invention, a positioning plate 140 positions the discharge electrode 130 on the electrode holder 170. This reduces inconsistencies in the positional relationship between the electrode surface 131 and the work-processed surface 12, enabling high-precision machining of the impeller 10. Furthermore, the position of the discharge electrode 130 can be finely adjusted by inserting a shim into the gap between the discharge electrode 130 and the positioning plate 140.

[0060] In an electrochemical machining apparatus 100 according to one embodiment of the present invention, the discharge electrode 130 is detachably connected to the electrode holder 170. Therefore, only the discharge electrode 130 damaged by electrochemical machining can be removed from the electrode holder 170 and replaced.

[0061] In an embodiment of the electrochemical machining apparatus 100 of the present invention, a second nozzle 136 disposed above the discharge electrode 130 has a second outlet 133 for ejecting electrolyte from between the upper counter electrode surface 131 and the work-on-machine surface 12. This allows for a more uniform distribution of electrolyte between the counter electrode surface 131 and the work-on-machine surface 12, enabling high-precision machining of the impeller 10.

[0062] In an electrochemical machining apparatus 100 according to one embodiment of the present invention, the discharge electrode 130 and the first nozzle 134 are integrally formed and detachably mounted together. Therefore, compared to the case where the discharge electrode 130 and the first nozzle 134 are integrally formed and inseparable, the discharge electrode 130 and the first nozzle 134 can be easily manufactured, and only the discharge electrode 130 damaged by electrochemical machining can be replaced.

[0063] In an electrochemical machining apparatus 100 according to one embodiment of the present invention, the discharge electrode 130 and the second nozzle 136 are integrally formed and detachably mounted together. Therefore, compared to the case where the discharge electrode 130 and the second nozzle 136 are integrally formed and inseparable, the discharge electrode 130 and the second nozzle 136 can be easily manufactured, and only the discharge electrode 130 damaged by electrochemical machining can be replaced.

[0064] In an embodiment of the electrochemical machining apparatus 100 of the present invention, when viewed from above, the second nozzle 136 is bent at the bend 137, and the second nozzle outlet 133 is located above the electrode surface 131. Therefore, it is possible to... Figure 4 As shown, when the electrode surface 131 and the workpiece surface 12 are close to each other and facing each other, the interference between adjacent second nozzles 136 is suppressed.

[0065] In the electrolytic machining apparatus according to the first modification, a flow rectification mechanism is provided in at least one of the flow paths of the electrolyte toward the first nozzle 234 at the first outlet 132 and the electrolyte toward the second nozzle 136 at the second outlet 133. As a result, the electrolyte can be evenly distributed at at least one of the first outlet 132 and the second outlet 133, allowing for a more uniform supply of electrolyte between the electrode surface 131 and the workpiece surface 12, and enabling high-precision machining of the impeller 10.

[0066] In the electrolytic machining apparatus according to the second modification, the first nozzle outlet 332 of the first nozzle 334 is composed of a wall surface 139 continuous with the electrode surface 131 of the discharge electrode 130, an opposing surface 332a in the first nozzle 334 spaced apart from the wall surface 139, a first connecting surface 332b and a second connecting surface 332c connecting the wall surface 139 and the opposing surface 332a. Therefore, the electrolyte ejected from the first nozzle outlet 332 of the first nozzle 334 can be continuously supplied from the wall surface 139 along the electrode surface 131 in a more uniform distribution between the electrode surface 131 and the surface to be machined 12, enabling high-precision machining of the impeller 10.

[0067] In the electrochemical machining apparatus according to the third modification, when viewed from below, the second nozzle 436 has a generally circular second outlet 433, and the opening area of ​​the second outlet 433 is relatively large. This reduces the flow rate of the electrolyte ejected from the second outlet 433 and allows for targeted supply of electrolyte to the portion between the electrode surface 131 and the work-processed surface 12 where the electrolyte ejected from the first outlet 132 is less likely to diffuse.

[0068] It should be considered that all aspects of the embodiments disclosed herein are illustrative and not restrictive. The scope of the invention is not shown by the foregoing description but by the claims, and is intended to include all modifications of the same meaning and scope as the claims.

[0069] Explanation of reference numerals in the attached figures

[0070] 10... Impeller; 11... Blade; 12... Machined surface; 100... Electrolytic machining apparatus; 110... Support platform; 120... Rotating shaft; 130... Discharge electrode; 130a... Main body; 131... Electrode surface; 132, 332... First nozzle outlet; 133, 433... Second nozzle outlet; 134, 234, 334... First nozzle; 134a, 234a... First engaging part; 135... Recess; 136, 43... 6...Second nozzle; 136a...Second engaging part; 137...Bend; 139...Wall surface; 140...Positioning plate; 150...Insulating plate; 160...Bolt; 170...Electrode holder; 180...Linear drive part; 190...Clamping mechanism; 231...Inlet; 232...First narrowing part; 233...Second narrowing part; 332a...Facing surface; 332b...First connecting surface; 332c...Second connecting surface.

Claims

1. An electrolytic machining apparatus for electrolytically machining an impeller with multiple blades roughly machined along its outer periphery. The electrolytic processing apparatus is characterized by having: A discharge electrode having an electrode surface along the machined surface of one of the plurality of blades; and A first nozzle, disposed adjacent to the discharge electrode, has a first outlet for ejecting electrolyte along the electrode surface between the electrode surface and the work-bearing surface. The discharge electrode is disposed only on one circumferential side of the impeller, relative to the aforementioned blade. The first nozzle is configured to spray electrolyte from the radially outer side of the impeller towards the electrode surface and the work-on-machine surface through the first spray outlet. The electrolytic processing apparatus also has a second nozzle. The second nozzle has a second spray outlet disposed axially above the impeller relative to the discharge electrode, from which electrolyte is sprayed between the electrode surface and the surface being processed.

2. The electrolytic processing apparatus according to claim 1, characterized in that, The first nozzle and the second nozzle each have an electrolyte flow path. The flow path of at least one of the first nozzle and the second nozzle is provided with a flow rectification mechanism.

3. The electrolytic processing apparatus according to claim 1, characterized in that, The discharge electrode and the second nozzle are integrally formed and can be detachably attached to each other.

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